Pressurized powder dispensing device



Feb. 4, 1969 R. H. ABPLANALP 3,425,600

PRESSURIZED POWDER DISPENSING DEVICE Filed Aug. 11, 1966 Sheet of 3 Feb.4, 1969 R. H. ABPLANALP 3,425,600

PRESSURIZED POWDER DISPENSING DEVICE Filed Aug. 11, 1966 Shget 2 of5INVENTORJ. BERT HENRY AQPLANALP Filed Aug. 11. 1966 Feb. 4, 1969 R. H.ABPLANALP 3,425,600

PRESSURIZED POWDER DISPENSING DEVICE Sheet 3 of 5' v INVENIOR] F- 3ROM-"RT HENRYABPI AMI/ WMW ATTORNEY).

United States Patent 3,425,600 PRESSURIZED POWDER DISPENSING DEVICERobert Henry Abplanalp, 10 Hewitt Ave., Bronxville, NY. 10708 Filed Aug.11, 1966, Ser. No. 571,824 US. Cl. 222193 '11 Claims Int. Cl. B67d 5/54,5/60; B05b 7/00 ABSTRACT OF THE DISCLOSURE Gas flow passages for theproduct container of a pressurized dispenser of the isolation type areadapted to assist in urging product toward a discharge ejector bycausing turbulent agitation of a powdered product and positive pressureassistance for a viscous product.

The present invention relates to an aerosol dispenser of the isolationtype having a construction that renders the dispenser particularlyuseful for the dispensing of powdered products. In this specificationand claims appended hereto, a dispenser of the isolation type comprisesa vessel containing pressurized gaseous or gasifiable liquid propellantwhich is mounted within, but otherwise is separate from a container forfluent product to be dispensed. The propellant and the product areisolated from one another until mixed at or near the discharge port ofthe dispenser in the course of discharge. In such dispensers, a valvelocated in the head structure of the propellant chamber normallyprevents outflow of the pressurized propellant, but on being openedpermits flow of propellant in gaseous (vapor) form to the dischargeport. By the action of an ejector (sometimes called a venturi near thedischarge port, to which separate flow lines from the product containerand the propellant container are respectively connected, the outflow ofthe propellant when the valve is opened, reduces the pressure in theproduct flow line and product container and a simultaneous outflow ofthe product is brought about. By suitably directing the stream ofpropellant into contact with the stream of fluent product,(conventionally by directing the propellant transversely across themouth of the product flow line) a spray discharge is produced.

Such a device is described in my copending application Ser. No. 521,885,filed Jan. 20, 1966, now Patent No. 3,326,469 issued June 20, 1967.

It'has been found that dispensers of the isolation type having meansproviding a positive flow of gas into the product container duringdischarge are particularly useful to dispense powdered products. In oneform of this invention of especial usefulness with powders, a gas flowsystem is provided which avoids contamination of the powder withmoisture.

'Because of the natural tendency of many powdered materials to cake andstack, the absence of a positive flow of gas into the product containerduring the dispensing step will often result in termination of orheterogeneous discharge of the powdered products.

It is a common observation that an unfluidized powder will tend to forma conical cavity about the entrance to a centrally disposed vacuumeduction tube. This phenomenon is referred to as cavitation. When thecavity extends below the entrance to the eduction tube, further powderdischarge will not occur until the agitational force restores the powderlevel above the entrance to the eduction tube.

With a positive how of gas passing into the product container, thepowder is continuously agitated during discharge, thereby fiuidizing atleast a portion of the powder and providing a continuous supply ofpowder to the prodnot flow line leading to the ejector. The gas flowalso acts as a carrier and thereby assists the discharge of powder.

According to the present invention, a powder dispenser of the isolationtype is provided having means for directing a stream or streams of gasat the powder supply with suificient velocity to agitate or fiuidize thepowder and thereby sweep the powder toward the eduction tube. The sourceof the stream of gas may be atmospheric air which enters the productcontainer through channels directed at the powder surface. The operationof the dispenser reduces the pressure in the product containersufficiently to draw air from the atmosphere through the channels withsufiicient velocity to accomplish at least partial fluidization of thepowder.

Alternatively, and particularly useful when product contamination withatmospheric moisture is to be avoided, propellant vapor may be directedfrom the propellant vessel upon actuation of the propellant valve tosupply the agitational force within the product container.

In the drawings:

FIG. 1 is a view in elevation of a powder dispenser according to thepresent invention showing a surrounding product container in verticalcross-section;

FIG. la is a sectional view taken on line AA of FIG. 1;

FIG. 2 is a view in elevation of another embodiment of the presentinvention showing a portion of a surrounding product container invertical cross-section;

FIG. 3 is a view in elevation of a further embodiment of the presentinvention showing the propellant chamber and a portion of the productcontainer in vertical crosssection; and

FIG. 4 is a view in elevation of a still further embodiment of thepresent invention showing a surrounding product container in verticalcross-section.

In FIG. 1 a product container generally designated as 20 surrounds thepropellant container 10, said container 10 being mounted within theproduct container by attachment at the mouth 21 of the product container20.

The propellant container 10 includes a head structure 12 (not shown indetail in FIG. 1) comprising a mounting cup for closing the top openingin the propellant container 10, a manually operable valve assembly forcontrolling propellant flow, and an actuator 25 which is mounted on avalve Stern extending through a central opening in the mounting cup. Theactuator has an ejector to which separate product and propellant linesflow. A product dip tube 11 communicating at its upper end with theproduct flow line which extends through the propellant container to theejector. A suitable propellant container and associated head structureis described in United States application Ser. No. 524,527, filed Feb.2, 1966, Which application is made a part of the disclosure herein.

The propellant container 10 is retained in the mouth 21 of the productcontainer by means of a head 22 formed in the exterior wall of thepropellant container 10 and a complementary groove (not shown in sectionof FIG. 1) formed in the interior wall of the mouth 21 of the productcontainer 20. Spaced about the periphery of the interior wall of themouth 21 of the product container are grooves or channels 23 whichcommunicate the interior of the product container 10 with theatmosphere, the channels 23 being directed downwardly towards thepowdered product 24.

The plurality of grooves 23 and their spacing is best shown in FIG. 1a.The grooves should be relatively small to accelerate the inflowing airto provide .a jet-like stream of incoming air.

Operation of the dispenser causes a drop in pressure in the productcontainer 20. The reduced pressure within the container 20 induces airto rush through the channels 23 and impinge upon the powdered product24. The air impingement continually agitates and redistributes thesurface of the powdered product mass 24 to prevent compacting orstacking of the powder. The fiow of air through the powdered product 24causes the individual powder particles to be surrounded and buoyed bythat air, inflating the mass and permitting the individual particles tomove with respect to one another with greater facility.

Another embodiment of the present invention is illustrated in FIG. 2.This embodiment is similar to that of FIG. 1 with the exception of thelocation of the air channels. In the embodiment of FIG. 2 indentationsof splines 29 are provided on the exterior wall of the container 10.These splines provide passages which communicate the interior of theproduct container 20 with the atmosphere. The splines cooperate with themouth portion 21 of the container to produce jet forming orifices.

In FIG. 3, the product container 20 is shown in partial section and thepropellant container is shown mounted in the mouth 21 of the productcontainer in a manner shown in FIG. 1. In FIG. 3 similarly numberedparts correspond to the parts set forth in FIG. 1. Now to be describedis a head structure, generally designated as 30, comprising a manuallyoperable valve unit attached to a mounting cup 31 which forms theclosure for the top opening of the propellant container and an actuator32 positioned in the valve stem 33 which extends through a centralaperture 34 in the mounting cup 31. The valve parts 35, 36, and 37comprise the gasket, valve housing and the body, respectively. The valvebody 37 has a central longitudinal passage 39 which extends through thevalve stem and communicates at its lower end with the product flow line9 and at its upper end with the ejector zone 40. The product flow line 9is sealed to the propellant container bottom by means of a tapered plug13. The product flow line communicates with a product eduction tube .11which extends into the product mass. The valve body 37 further has alongitudinal passage 41 which surrounds the longitudinal product passage39 and communicates at its lower end with the opening 38 in the valvebody and at its upper end with the passage 42, which passage 42communicates with the ejector zone 40 through passage 43.

The actuator 32 is of the construction set forth in application Ser. No.524,527 referred to above, and further comprises an annular laterallyextending portion 46 and an annular skirt 47 depending from the lateralportion 46. The lower portion of the skirt 47 has an annular bead 48which mates with an annular groove 49 in the exterior wall of the mouth21 of the product container 20, thereby mounting the actuator 32 to theproduct container 20 and forming the closed chamber 45. The actuator 32is fabricated of a material that will permit downward movement of theactuator relative to the product container so as to actuate the valve.For example, the lateral portion 46 may be constructed of a relativelythin section of plastic, such as, nylon or polyethylene, such that uponfinger pressure to the surface 50 the lateral portion 46 will flex in adownward direction.

In the valve stem 33 is an opening 44 which permits bleeding ofpropellant from the passage 41 to the chamber 45 defined by the actuatorand its associated lateral portion 46 and skirt portions 47. The bleedpassage 44 is of a controlled dimension which permits passage of alimited amount of propellant from the passage 41 to the chamber 45 andultimately through grooves 23 into the product container 20 whereat itacts to agitate the powder 24 (not shown). The amount of propellantpassed through the opening 44 should be limited to permit a sufficientquantity of propellant to pass into the ejector zone 40 so as to effecta pressure drop in the product lines 11 and 39. The amount of bleed offto permit optimum efficiency for each powdered product may be determinedby simple experimentation. It has been found that with a powder having agrain size below 60 mesh, an orifice of .010" in a valve stem having aproduct passage of .050 in diameter will satisfactorily agitate thepowder and still produce adequate pressure drop in the product line; thepropellant being under a pressure of 70 p.s.i. at 70 F., and the lengthand inside diameter of the product flow line being 7.0 and .070",respectively.

As an alternate to the opening 44 which may be one or more openings, theexterior of the valve body 37 and its associated valve stem 33 may haveone or more grooves or splines which communicate with the propellantcontainer 20 and the chamber 45 upon actuation of the valve.

In operation finger pressure on the actuator 32 will depress the valvebody 37 and peel back the gasket 35 in a known manner so as to bring theopening 38 into communication with the propellant vapor. The vapor willpass into the passage 41, through the passages 42 and 43 to the ejectorzone 40. The flow of propellant through the ejector zone 40 will cause apressure reduction in the product flow lines 11 and 39 and effectproduct flow through 11 and 39 to the ejector zone 40, whereat it isdischarged to the atmosphere. Moreover, a portion of the propellantpassing through passage 41 will exit through the opening 44 into thechamber 45 from whence the propellant passes through the grooves 23 intothe product container 20, whereat it provides an agitational force forthe powder.

With the structure of FIG. 3, the powder may be agitated withoutintroduction of atmospheric moisture. A further advantage is that thepropellant acts as a fluidizer of the powder with all the attendantadvantages of a fluidized system for conveying a powder. Proportioningof the bleed passages 34 and channels 23 will provide adequate downwardvelocity for the propellant vapor.

It should be noted that the embodiment illustrated in FIG. 3 may also beused to assist the dispensing of viscous liquid products. The propellantbleed passages are then proportioned to provide a pressure within theproduct container somewhat in excess of atmospheric pressure to assistin forcing product up the eduction tube 9.

The embodiment shown in FIG. 4 includes a distribution tube 26 forintroducing gas to the powder mass 24 which communicates at its upperend with the groove 22 and extends downwardly into the powder 24. Thedistribution tube may be transversely perforated with small apertures 27to introduce gas to the powder mass 24. The embodiment of FIG. 4 may beemployed with tan atmospheric communication at the upper end of thedistribution tube 26 as it is illustrated, or may readily be adapted tothe propellant bleed system illustrated in FIG. 3 wherein thedistribution tube 26 would be used in lieu of channels 23 shown in FIG.3.

I claim:

1. In a dispenser of the isolation type wherein powdered product andpropellant are stored in separate containers each provided with separateflow lines leading to a discharge ejector, the improvement comprising aninlet in the product container open at one end to the atmosphere and incommunication with a passage for directing a stream of air to theproduct with sufficient velocity to agitate the product to. aid its flowto the ejector, said air stream being effected by a reduction ofpressure in the product chamber during discharge of the product.

2. In the combination of a container having a powdered product thereinand a valved propellant container having a venturi discharge ejector inthe valve actuator which dispenses the powder by suction and ejectionaction, the propellant container being mounted within a top opening ofthe powder container, and wherein separate powder suction and propellantpressure flow lines are established between the respective containersand the ap propriate chambers of the ejector, the improvement comprisinghaving at least one conduit to the powder container for directing astream of propellant gas at the surface of said powder at a velocitysufficient to agitate the powder.

3. The combination of claim 2, wherein the conduit is open at one end tothe atmosphere and the gas is air drawn through the inlet by eifecting areduction of pressure within the product container during discharge ofthe product.

4. The combination of claim 3, wherein the conduit is a groove in theinterior wall of the mouth of the powder container.

5. The combination of claim 2, wherein the conduit is a groove in theinterior wall of the mouth of the powder container.

6. In the combination of a container having a powdered product thereinand a propellant container having a head structure in the top of thepropellant container comprising a valve unit for controlling propellantflow and a valve actuator having a venturi discharge ejector therein,the propellant container being mounted within a top opening of thepowder container; and wherein separate powder suction and propellantpressure flow lines are established between the respective containersand the appropriate chambers of the ejector, the improvement comprisinghaving at least one inlet to the powder container and at least onepropellant vapor port in the propellant flow line, and a passagecommunicating the inlet to the product container and the propellantvapor port and directed at the powder surface so that upon actuation ofthe propellant valve a portion of the propellant vapor will pass intothe passage to the product container with sufficient velocity to thereinagitate the powder.

7. The combination of claim 6, wherein the product and the propellantcontainers are mounted at their respective top side portions and whereinthe separate prodnet and propellant flow lines extend longitudinallythrough the valve unit including the valve stem, and further wherein thechamber is formed by a lateral flexible portion extending from theactuator and an annular skirt portion depending from the lateralportion; said skirt portion being hermetically attached to the exteriorside wall of the product container.

8. The combination of claim 7, wherein the propellant vapor port is atransverse opening in the exterior wall of the valve stem whichcommunicates the propellant flow line in said valve stem and thechamber.

9. The combination of claim 7, wherein the propellant vapor port is alongitudinal groove in the exterior wall of the valve stem whichconnects the interior of the propellant container and chamber uponactuation of the valve.

10. In a dispenser of the isolation type having a closed productcontainer, a valved propellant container, a valve actuator having aventuri discharge ejector, and a propellant pressure flow line separatefrom a product suction line each of said lines leading from theircontainers to the appropriate chambers in the ejector,

the improvement comprising a conduit to the product container incommunication with the propellant flow line at a point beyond the valveto effect an increase in the pressure in the product container abovethat of the product suction line during discharge to assist the ejectorin extracting the product.

11. The dispenser of claim 10, wherein the product is powdered andwherein the inlet is in communication with a passage for directing astream of propellant gas at the product with suflicient velocity toagitate the product during discharge to assist the ejector in extractingpowdered product.

References Cited UNITED STATES PATENTS 2,696,933 12/1950 Barclay et al.222193 X 2,781,154 2/1957 Meredith 222193 3,289,949 12/1966 Roth 239308X 3,291,346 12/1966 Marrafiino 239-308 X FOREIGN PATENTS 638,023 4/1962Italy.

ROBERT B. REEVES, Primary Examiner. H. S. LANE, Assistant Examiner.

U.S. Cl. X.R. 222-495, 464; 239-308

